Wash the potatoes and cucumbers thoroughly, peel them, and slice thinly.
Boil the potatoes in water for 5 minutes, then drain in a sieve to remove excess moisture.
Sprinkle salt on the cucumbers and let sit for 5 minutes, then gently squeeze out the moisture.
In a bowl, combine potatoes, cucumbers, red pepper paste, vinegar, sugar, minced garlic, and sesame oil. Mix evenly.
Place in a serving dish and sprinkle with sesame seeds to finish.